July 12, 2008

RFID Read Range: Just how far can RFID track something?

Tomorrow, we will be announcing the new AD 224 RFID chip from Avery Dennison will be used in our Pro-Tags DoD product lines and our premier Nox-1 Asset Tracking products.

We have been testing the new 224 RFID chip since April 2008 and, as far as Passive Generation 2 RFID technology goes, it is superior in performance and durability to anything on the market.

Our tests show the new 224 averages over 40' effective useful range. This means, we can create reliable solutions within that 'zone'. There are many caveats to this (tag density, personnel movement), but it's a relative distance to other tested tags. Four years ago, the average was about 10' effective.

Attached is a graph of our performance tests.

How to interpret this:

Difficult: Liquids / near metal situations or edge-on reads. Todays latest Gen 2 passive chips are strong enough to handle most difficult mounting situations and start around 10' readability. The 224 is beyond 20' in difficult situations. We typically plan for difficult as our working range.

Average Max: Most tag mount situations are 'average'. We typically deploy/test in difficult because the environment will change over time. With the 224, we can plan to have an effective working range of 40' and be confident we will achieve 100% reads.

Free Space: If we do some minor optimization ( ensure tags are facing readers, give clear line-of-site), we can design solutions that will work 100% of the time @ over 60' using the AD 224. Free space is an unlikely scenario -- however, we do create traps based on free space when we need longer range surveillance.

Optimized: This just tests the maximum range of the tag. To create an optimized environment, we need a clear view of the tag, metal reflectors to help signal bounce and a low-noise environment. Rarely can we make an optimized situation in a deployment -- but, when we need to (long range surveillance on an item), we can. In fact, this optimization can use RFID as a trip-wire because any disturbance in the force will cause loss of tag view. (Note: Optimized is not a realistic test result. It's just for fun. Don't plan on this type of range.)

Test Note: Testing done on the ThingMagic M5 Reader. We've tested other readers and they all show lower performance / read range capability. 'Other' listed in chart is the best performing competitive tag we tested. Other tags were tested but performed below or 'at' the AD222 in capability.

So, more to the point, how far can we track you or an item you are carrying with RFID? Typically, about 40'. And, absolutely within 20'. But, as much as 120'. This is using a < 20 cent (quantity 1,000,000) RFID tag. [Side Note: Active RFID is different and would cost $20+ per tag and give several-hundred feet of tracking capability... Your Cell Phone is trackable (accurately) to over 5 miles...]

We have been working with Avery Dennison for a couple of years and the tags they provide are outstanding, under 0.1% failure, backed by a solid, profitable company, and extremely durable. If you're buying research reports or trying to decide if RFID works -- why? It works. We guarantee it. (See "How to get started" when you follow the link).

Comments

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The test results shown are flawed. I believe the person testing experienced skip waves off of material in the area giving erroneous results. You should retract the report as it is misleading to the industry, Avery and customers.

Please elaborate on which part you are concerned with and I will elaborate on the test results?

Maybe I should re-clarify:
In our findings, as referenced above, we 'plan' on 40' effective range. The 'stuff beyond' is really just for fun and, perhaps that's your point? If so, I totally agree and I apologize if it sounds like we are advocating RFID planning beyond 40'. Don't do it... Yet.